Credit balance mechanism



y 4, 1954 R. E. BOYDEN ETAL CREDIT BALANCE MECHANISM 7 Sheets-Sheet 2 Filed March 25 1950 bum May 4, 954 R. E. BOYDEN ETAL 2,677,499

' CREDIT BALANCE MECHANISM Filed March 25, 1950 7 spews-Sheet 3 lA/l/ENTO/FS. Beam 7 5. Ba roe/v Hu an L. CHI/Pr Pump 5 Eur/N Pouwr D. Gun/awe Emu/mo S, Nan/r BY V/lmrav. ,4. H190:

ATTORNEY y 1954 R. E. BOYDEN ETAL CREDIT BALANCE MECHANISM 7 Sheets-Sheet 4 Filed March 25 1950 mm m m y M-UHLH flm w hm /m m i 2 NW k Q mmw "N $wwm M 1 u 7 y 4, 1954 R. E. BOYDEN ET AL CREDIT BALANCE MECHANISM 7 Sheets-Sheet '7 Filed March 25, 1950 /N VE N TOR S Rose-RT 5. Bo mew Hus/4 L. Cum Play/mo E. AK/N Pose/er Q GLENN/E Flam/P0 5. MARK B Y Mwm nw A. PAksM/S M fix M Patented May 4, 1954 UNITED STATES PATENT OFFICE oaEm'r BALANCE MECHANISM Application March 25, 1950, Serial No. 151,896 I This invention relates to adding and calculating machines and has particular reference to calculating machines of the'type capable of automatically computing true negative totals as well as true positive totals.

The principal object of the present invention is to provide an improved mechanism for obtaining a. true negative total or a true positive total in a single machine cycle without having to take preceding blank or other preparatory machine cycles.

Another object isto provide an entirely automatic mechanism for taking true negative totals or true positive totals, whichever is required by the condition of the machine, without any attention from the operator other than to cause operation of the usual total efiecting controls.

Another object is to visually indicate an overdrafted condition of the calculating machine.

Another object is to automatically arrest operation of the machine upon occurrence of an overdraft.

Another object is to provide a credit balance control mechanism which is simple and economical to manufacture. l c

The manner in which the above and other objects of the invention are-accomplished will be readily understood on reference to the following specification when read-in conjunction with the accompanying drawings, wherein: c

Fig. 1 is a longitudinal, sectional view through an adding machine embodying the present invention. a

Fig. 2 is a transverse sectional view through a part of the keyboard of the machine and is taken along the line 2-2 of Fig. 1.

Figs. 3 and 4 are side elevation views of the accumulator control mechanism.

Fig. 5 is a side elevationview illustrating the clutch controls and the mechanism for indi eating an overdrafted condition-of :themachine.

Fig. 6 is a fragmentary side elevation view showing a modified form of the invention.

Fig. 7 is a side view, in section, of the accumulator and is taken substantially along the line i'! of Fig. 9.

Fig. 8 is a side view, similar'to Fig. '7, but illustrating the lowermost order of the accumulator and is taken substantially along the line 8--8 of Fig. 9.

Fig. 9 is a front view of the accumulator, with the tens transfer shaft deleted, and is taken substantially in the direction of the arrow 9 in Fig. 8.

Fig. 10 is a fragmentary side view of the lower- 2 most order of the accumulator showing the same in a negative overdrafted condition. V

Fig. 11 is a side view of the transfer shaft centralizer mechanism.

Fig'. 12 is a side view of the tens transfer shaft drive mechanism. I

Fig. 13 is a view taken along the line I 3-43 of Fig. 12 showing the means for disabling the tens transfer shaft drive.

Fig. 14 15a sectionalfplanview taken substantially along theline I l-+14 of Fig. 12.

Fig. 15 is a sectional view of the Geneva drive and is taken alongtheline l5--|5 of Fig. 14.

Fig. 16 is a side view illustrating the rack drive mechanism.

Fig. 17 is aside elevation view of the symbol printing control mechanism.

Reference is hereby made to the co-pending application of Robert E. Boyden, S. N. 582,553, filed March 13, 1945, and since matured into Pat. No. 2,583,810, issued on January 29, 1952, for a complete disclosure of the adding machine in which the present invention is embodied. Therefore, for the sake of brevity, only that mechanism which embodies the present invention or cooperates therewith will be illustrated and described in detail herein. Also, the specific form of accumulator disclosed herein is disclosed and claimed in Patent 2,472,696 issued on June 7, 1949, to E. P. Drake. It should be understood, however, that the invention may equally well be applied to other forms of adding and calculating machines and to other. forms of accumulating mechanisms.

General structure and operation In general, the machine is of the full keyboard type comprising a series of rows of amount keys, each row including nine keys 9 ranging in value from 1 to 9 for controlling entry of digits into an associated denominational order of the machine. A series of depressible control bars are provided causing the machine to perform various functions. Among these bars is an add bar i0 (Figs. 1 and 5) effective to cause operation of the machine to add amounts into an accumulator, generally indicated at 2 and also to print this amount on a paper strip 12a fed over a platen l2. cause operation of the machine to subtract an amount set up on the keys 9 from an amount in the accumulator. A non-add bar [4, upon depression, causes operation of the machine to print an amount set upon the keyboard without entering the same in the accumulator.

A subtract bar 13 is provided to.

When it is desired to obtain a net total of a number of items entered into the accumulator, a total bar I! is depressed. This will cause the machine to clear the accumulator to zero and print the total. In the event it is desired to obtain a sub-totaL-a sub-total bar 18 is depressed, causing the machine to print the total but retain the amount in the accumulator.

Operation of the machine is divided into two phases and during the first phase of a machine cycle in adding or subtracting amounts into the machine, ordinally arranged'actuating racks I8 are difierentially advanced under control of depressed ones of the keys 9. During suchadvance, the racks drive the difierentorders of the accumulator 2 accordingly. At approximately mid cycle and after the racks have been differentially advanced the printing operation occurs to print the amount on the tape I2a. In totaling and sub-totaling operations the racks are also advanced during the first pheseand in this case they are differentially arrested by the accumulator when the various orders thereof reach zero positions. p o

The. accumulator employs a' positively operated subsequent tens transfer mechanism and it.is

during the second phase of a machine cycle and uri g return of the racks to their original positions that'thls mechanism is, normally operated to. effect tens transfers. During credit sub-total operations of the machine, however, the operation of the tens transfer mechanism is suspended as will beseen later on. V I Twosuccessive tens transfer operations occur during the second phase of all machine cycles except credit sub-total operations. The. second transfer operation normally operates idly but becomes eifective upon an overdraft to enter a fugitive one. into the lowermost order of the accumulator, eitheradditively or subtractively, depending on whether an additive or subtractive overdraft occurs. Thus any tens transfers conditioned by such entry of th y fugitive one are also consummated during this second transfer operation. v 7

Means are provided for visibly and physically indicating the occurrence of an overdraft in the accumulator. A visual indicator automatically appears whenever a negative overdraft occurs and remains in appearance as long asthe machine is in such condition. Also, operation of the machine is arrested whenever the machine overdrafts either positively or negatively. The latter facilitates performing division operations in that the operator may merely repeatedly sub tract the divisor from the dividend until the ma-- chine stops as an incident to a negative overdraft.

Keyboard The keyboard is of the flexible type and each amount key 9 (Figs. 1 and 2), when depressed, serves as a stop against which an associated shoulder ISI of an aligned rack I9 limits during advance of the latter.

Each of the keys 9 is guided in aligned slots formed in a keyboard frame comprising a top plate 2I and a bottom plate 22. The keys. in each bank are yieldably pressed upward by a tension spring 322 extending the length of the keyboard and suitably attached at opposite ends to the top plate M. The spring rests on cross ribs 23 formed across slots 24 in the plate 2I and extends through openings in the different keys. Upon depression of a key the adjacent portions of the spring are stretched and extend down- Means are provided for locking the keys 9 in their depressed positions and for releasing any depressed key. Each key stem has a cam lobe 35 which, when the key is depressed, rocks locking. bailifi about trunnion bearings 31 on opposite ,ends' thereof. ".At' the bottom of its stroke, the cam lobe passes below the locking bail, enabling the latter to retract partially under the action of a spring 38 to a position where it latches the key depressed.

A stop 3.6aisformed on each locking bail 3:3,

' and when no keyS in any one order is depressed,

, the ball 36 of that order will be spring held in an extreme inwardly rocked position in which the stop 36a lies directly in front of one of the shoulders ISI of the associated rack I9 thereby preventing any-substantial forward movement of the rack during subsequent operation of the mashoulders m are-a1ternatelyarranged on the two parts. These shoulders are arranged to engage tips Scot thekey stem. which this. are arranged on alternate key stems to engage one of therackparts. .1

As shown narticula yin Fig. .5... thestems of the various control bars, I0, I3,; I4, I 'I and I8 are also slidahly mounted in slots provided in the plates 2I and 22. 1

' Rack. drive The present machine is driven by an electric motor (not shown) suitably connected to the driving side of a cyclic clutch generally indicated at 49, the driven side of which is secured to a shaft 5I. 1/

The clutch is controlled by a clutch dog 4! pivoted at 42 and normally held by a spring 43 in position to hold the clutch disengaged; Engagement of the clutch is effected by rocking the dog 4| counterclockwise.

Means are provided under control each of the control bars I0, I3, I4, I1 and I8 causing engagement of the clutch 40 and operation of the machine. As shown in Fig. 5, a clutch control bar 323 is mounted under the control bars and is provided with slots slidably guided on frame pins 324 and 32-5. Inclined camming slots 26 are formed in the bar 323 directly under pins 145, I46, IBI, and I62underlying and actuated'by the control bars I3, I4, I'I'and I8 respectively. Each of the pins is mounted on an arm I44 pivotally supported on a frame pin I41 and urged counterclockwise by a spring 21 extending between the arm and a frame stud, i. e. 28, to normally hold the associated bar in raised position. A hook 29 is pivoted at'30 to an ear of slide 323 and is normally held by a spring 3| in engagement with a pin 32 carried by the upper end of the clutch dog. Thus, depression of any of the control bars I3, I4, I! and Ia'efiects a forward movement of the slide to rock the clutch dog M and thus cause engagement of the clutch.

The add bar III is likewise capable of causing engagement of the clutch through the slide 323 and for this purpose the stem of bar In is formed to embrace a rod 33 carried by spaced arms 234 fastened to a rock shaft 235 pivotally mounted in a manner not shown on the frame of the machine. The rod 33 is arranged in oamming relation to an inclined surface 236 formed on the slide 323 whereby depression of the bar against .the action of asuitablejspring-(not show) will pendently transmitting a drive from the shaft 5i to the various .drive racks .19. Referring to Fig. 16, a pair of juxtaposed complementary cams 43a and 43 are keyed ontheshaft 5!. These cams are engaged by rollers .44 and 45, respectively, mounted on a ca'mfollowerfi, pivoted at 41. Thecam followermovesbetweenthe cams and is connected by alinkltto arm 49 secured to arock shaft'50.... The' armis: bifurcated to embrace a' roller 35l rotatablymo'unted on one end of a rack drive shaft 52.- The roller is also guided for fore andaftmovement .within alongitudinally extending guide 'slot 53 inamachine side frame plate 54.. A similar roller (not shown) is provided onthe'oppositeend-of the shaft 52 and is embraced by an'arm similar tov arm 49 fixed to the shaft'50'to insure parallel movement of the shaft 52 during its rackdriving movement.

Referring to Fig. 1, each ,of the .drive racks 19 has an elongated'slot55,embracing the shaft 52 whereby tosupport the forward end of the rack, the opposite end of the rackhaving a slot 238 slidably supported on across rod'239. The slot 55 in each rack terminates'in'opposed lateral depressions 56 at its closed .end and each of these able connection between the shaft and the drive rack.

When, during forward movement of the shaft 52, a rack l 9 is stopped upon striking a depressed key stem 9a or the associated zero stop 36:: or by the accumulator in totaling operations as will be described later, the rollers 51 will ride out of the depressions 56 against the action of spring 59 thus breaking the connection between the shaft and the racks. v

A rack gear section 62 is formed on the upper edge of each rack for the purpose of meshing with one of a series of pinion assemblies entrained with the printer mechanism'as will be described later. a pair of opposed rack gear sections 53 and 64 disposed on opposite sides of an associated accumulator gear 65, the latter forming part of the accumulator 2.

Printer The printer (Fig. 1) which will be described in general only, comprises a series of numeral Also, formed on each rack are printing wheels 68, one operatively connected to each of the drive racks [9 as will appear presently. Each numeral wheel has thereon a series of type ranging from 0 to 9 and these dials are so connected to the associated racks thatthey will print a digit corresponding to the value of the key depressed in the associated key bank or to the numerical position to which the-rack is moved in its forward stroke. Each wheel is rotatably mounted on a separate lever 81 which is loosely keyed on a printer control shaft 68 and spring urged clockwise by a tension spring 69 extending between the lever and a frame stud ill. Each printer wheel has secured thereto a gear H normally in mesh with a gear 12 also rotatably mounted on the associated lever 81. When the lever 61 is held in its normal positiqn as illustrated by the shaft 68 the gear 12 is meshed with an aligned one of a series of large idler gears '13 rotatably mounted on a cross shaft 14.

The latter idlersare continuously entrained with .controlshaft. 68 is rocked'clockwise by a suitable .mechanism (notshown) permitting the springs 10 to rock the printer arms-jland thus carry the .printing wheelsfiiforwardlyinto the dotanddash line positions 56a. intocontact with a printingribbon l6 and the paper strip in whereby to printthe number-registered on the dials onto the paper. Thereafter, and before the racks are returnedfrom theirforward advanced positions the shaft 58 is rocked counterclockwise to return the levers to their illustrated positions wherein the gears 12 are remeshed with the idlers'l3.

4ccumulator Referring in particularto Figs. 1, 5 and '7 to 10, inclusive, the accumulator generally indicated at 2 is arranged to beraised or lowered from a nor mal neutral illustratedposition for the purpose of engaging the various. accumulator gears with'either the upper rack sections 63 or the lower rack sections 64 of the :racks 19 in accordance with the type of problem to be performed. During an additive operation theaccumulator is raised to mesh the gears 65 with the rack sections 63 whereby the gears will be-rotated in a counterclockwise direction during subsequent forward digitizing movements of the racks whil during a subtractive operation the accumulator is lowered to mesh the accumulator gears with the rack sections 64 so that digitizing movement of the racks will drive the gears in a clockwise direction.

The accumulator comprises a shaft 11, supporting the hereinbefore mentioned accumulator gears 65, and a second shaft 18, both shafts being mounted in bearings formed in a series of cross plates 19 rigidly held in spaced relation with each other by suitable interlocking combs well knownin the art. A rod 8i is passed through the various plates 19 adjacent each comb to hold the latter in place. The shafts 11 and 18 are guided for vertical movement, to likewise carry the accumulator unit in vertically extending slots one of which is shown at 822 (Fig. 4) in a side frame plate 54 of the machine.

For the purpos of raising and lowering the accumulator unit in accordance with the type of problem to be performed, there is provided a box cam 82 (Fig. 3) pivoted on a, frame pin 83 and having a cam groove 84 embracing a roller rotatably mounted on one end of the accumulator shaft 11. Clockwise rocking movement of the cam 82 beyond its normal central illustrated position will raise'the accumulator in its adding position while counterclockwise rocking move ment of th cam will lower-the accumulator into subtractive position. A second cam I82 (Fig. 12) is provided to support and move the opposite end of the accumulator shaft in precisely the same manner. In order to insure parallel movement of the accumulator in its vertical travel a rock shaft 2 is rotatably supported in frame bearings (not shown) and is suitably secured at opshaft "I9 of the -aifcurnulator.

against the pawl by a spring 92I.

tion or ten teeth state as the {result of accumulatin'g te'n digits 'it "n'di'ti'cin's a ten transfer mechanism to siibsefi'uently enter the digit into the gear T65 of the heft higher denominational order to the left; this purpose a transfer pawl I81 *i's primate, being capable of rotating its associated "gear anin'crer'nent 6r 'ohe tooth space in either direction.

Each pawl surrounds its associated gear 65 and is pivoted on one side thereof at 85 to a cam follower lever 89 pivotally mounted on the lower The lever 86 is provided with a roller 81 adapted to be engaged by an aligned oneof a series of tens transfer cams 89 to be describ'ed'in detail hereafter.

Each pawl I84 is provided with three detent notches 99, the central one 'of which is normally engaged by a dentraliz'er lever 99, pivoted at 9| on the associated brace plate 19, and pressed In addition to holding the pawl I9 ilnahy of three positions about pivot 85, the 'c'entralizer 90 is also effective to normally maintain the pawl in a rearward positionsho'wn in Figs. '7 and 8.

Each gear 65, h; it rotates in "a clockwise direction from its "herb" position illustrated in Fig. 7 to its nine 'po'sit ioh in a subtraction operation carries a teeth 92 integral therewith into engagement with an ear 93 on the transfer pawl I84 associated with the nexthigher denominational o der of the accumulator. The tooth 92 thus rocks the pawl I8 4 upwardly about its pivotal support 85 into a position corresponding with the dot-dashlineposition 8411 in Fig. 8. As the pawl I84 reaches its upper position it is detented therein by engagement of the centralizer 90 with the lowermost detent notch 89. In this position of the pawl the tooth 93 will be positioned clear of the transfer tooth 92 so that the gear 65 may continue its rotational movement without interference between the teeth 92 and the ear 93. Also, in this position of the pawl I84, a transfer tooth 84b thereon is located directly behind a tooth 94 of the 'gear 65 so that in the subsequent tens transfer phase of operation in which the cam follower arms 85 are sequentially rocked by the cams 8 8 to advance the pawls I84, the tooth 841) will engage and drive the gear 65 one tooth space in a clockwise or subtractive direction.

Likewise, in additive operations, and when an accumulator gear 95 rotates counterclockwise from a nine position to a zero position the tooth 92 thereof will strike the ear 93 of the transfer pawl I84 in the next higher order, moving the latter to a lowermost position similar to that illustrated in full lines in Fig. 10 in which the centralizer '99 will engage the uppermost detent notch 89 of the pawl. Since the pawl I84 is symmetrical, exactly the same action will occur as in subtractive transferring operations except that thwart "5b wm be'rtta "t1 the tbtth in a 'countercleckwise bb'ahditrve'a ea t a It will be noted thatduring additive. subtractive and 'totalih 'dhtratiohs the hbc'uniulelior will be disengaged froth the 3. e, be returned its hehtifali'fis'ltioh in Fig. 1 prior to the trahsfe'r which occurs late in the machiheyfire, 'rheregb e, attir t e of digitizing ph 'e "of the'iycl ethe transfer hams I84 in all the b de'ilshhicharejo receive a tens transfer WiIIfie' coIrZiitionedhr ldcflg'tt'd an upper lover ibeitibh s ei sfi'e m en. the t me Of operation andfthe'aceumtilathr ti ers will become y d 1fi h b fiF i e t e. r vid f 'd n a er cti a tens transfer in the brders ofthe ma chine b h ii ia til ibv f i :Qr i t order, when viewing the machine from the front,

as 3 8: l iafl' i t Shaft 95, suitably s'upportedin Bearingscarri'ed by the side frame plates fertile mac ne, has secured thereon the various transfer htinest. The vanous 'eitcpt the carn '88c f(1 fig. ,il) jsshticiated with the ite has -ot e ve "substantially diax'netrica it dep sed 1b es tlieron, the cams arearjr'anged in 'a ehht row 'about the transfer shaft 99 at at to seqi fehtially actuate the various hath I flfr'ifrfdg'r mg I join, the lowermost o er 6h inward the We series bt t m obes being reflective to 'caftiseitwo SiITITGEQSWetEIiStranS- fer waves the "lf iilatc'irduri ngi each tens, transfer phase. It 'siiqiiid fbhqt' a that the lowermost order jihgi itt'a 'cam Illl'd is ar ranged to cause a t hfs lfraiisfer at the beginning of the sec-6nd transmi ave. the huh-565e of which will be described lbnn'tioh with the credit balance mechanism h It will be, hated thatthejdehtiauze s at and the levers- 8B 'fo'r'rn substantially parallel arms to carry the tranffer path 184 through paths which closely approxim te "a straight line rnotion regardless of the angular pesiti'o'n of each pawl about its pivot gt as the latter is actuated by its associated cain. During a'n idle transfer stroke, i. e. when a. pawl is hot ineondition for transfer, the latter will travel through, its stroke without engaging htsgeittajgeat 65 but during a transfer strike in which the pawl has been conditioned to causea trahsfer, fine or the other ofthe ears band 84}: of the pawl will advance the gear one increment ortooth. During such driving inoverheht, whichever tooth of the pawl is driving the gear will be engaged asucceeding tooth of the pinion and will be gradually shifted thereby into its neutral position so that, regardless of whether an additive or subtractive transfer is being made, the pawl will always come to rest in its neutral position.

A yieldable centraliz'er pawl 99 is provided to hold each accumulator gear in any registered position. As shown in Fig. 7, the pawl 96 is pivoted at the same point 9I as is the centralizer and is yieldably held in engagement between two teeth of the gear 65 by a spring 91.

Means and provided fer normally rotating the transfer shaft the latter part of a machine cycle and the digitizing phase has been completed, this mechanism being disclosed in Figs. 12 to 15 inclusive. As illustrated in Fig. 12, a mutilatedgear98 and a pair of discs 99 and I00 are secured together rivets I9I and keyed to the drive shaft 5| The gear 98 is normally aligned with and adapted toinesh with a mutilated pinion I 02 rjdtfatably and slidably mounted on a frame pin I03. gear 98 and;

pinion I02 form a geneva or intermittent drive mechanism. It will be noted that'the pinion I02 is provided with two gear portions, the left hand portion I02a (Figs. 13 and 15) being mutilated with the mutilated section normally riding on the periphery of the disc I00. The disc I has a cut-out portion I00a arranged to register with the gear portion I02a when the teeth of gear 80 become meshed with the right hand portion of the pinion I02 so as to permit rotation.

The length of the toothed portion of gear 98 is such that the shaft 95 will normally be rotated one complete revolution during every machine cycle, except during credit sub-total cycles as will appear hereinafter, and by virtue of the double lobed cams 88, each of the transfer pawls. except that associated with the lowermost order, will be actuated twice during each transfer phase.

It should be noted that the shaft 95 is rotated in a clockwise direction and that the transfer cam 88 associated with the order directly above the lowermost order will be the first to effect the transfer stroke of its associated pawl I84. The cams 88 are so angularly spaced about shaft 95 that any one cam will effect a transfer stroke of its associated transfer pawl before the next adjacent higher order camwill become effective to cause its transfer pawl to move.

' Means are provided for laterally shifting the pinion I02 into and out of mesh with the gear 98 so as to suspend tens transfer operations during credit sub-total operations of the machine. The pinion I02 is provided with a circumferential groove therein to receive a shifter I08 pivoted at its upper endon pin I 01 carried by a bracket I08 suitably secured to the machine side frame 54. The lower end of the shifter is guided in a slot I09 provided in an ear extending from the bracket I08.

The shifter I06 is provided with a cam slot I I0 registering with an elongated linear guide slot I I I in the bracket and both slots receive a roller IIZ rotatably mounted on an arm II3I secured to the aforementioned box cam I82.

It will be recalled that during add operations, the box cam I82 will be rotated clockwise from its illustrated neutral position to raise the accumulator and in so doing it will cause the roller I I2 to move downward along the slots IIO and III and thereby cam the shifter I06 to the right in Fig. 13 so as to de-mesh the pinion I02 from the gear 98 and align the section I02a of the same over the periphery of the continuous disc 98. However, normally, except in credit sub-total operations, the box cam I82 will be returned to its neutral position before the transfer phase occurs, permitting the pinion I02 to be meshed with the gear 98 during the transfer phase. A spring II II extending between the shifter I06 and bracket I 08 continually biases the shifter to the left in Fig. 13 to take up any lost motion intermediate the roller H2 and slots H0 and I I I. In credit sub-totaling the accumulator will be held in its raised position throughout the transfer phase. Thus the tens transfer drive will be rendered ineffective during such operations.

During subtract and positive totaling and subtotaling operations, the box cam I82 will be rotated counterclockwise to lower the accumulator into mesh with the lower rack sections 64 (Fig. 1) of the racks I 9 and, consequently, the roller II2 will be raised along the slots H0 and III. However, it will be noted that the upper portions of these slots are normally in direct alignment with each other and, therefore, the pinion I02 will remain in its position shown during such for transferring a fugitive one from the higher'-' most order of the accumulator to the 'lowermost order upon occurrence of an overdraft. That is, when the amount beingsubtracted becomes greater than that registered by the accumulator a negative overdraft will occur, and the accumulator gears in orders to theleft of those being digitized will turn from zero" to nine registration. This action will occur during the first transfer wave effected by the first series of cam lobes on the transfer cams 08, and upon such occurrence, the tens transfer pawl "Ma-(Fig; 8) associated with the lowermost order accumulator gear will be conditioned for transferring operation. Thereafter, the second transfer wave effected by the second series of cam lobes on the cams 88 will cause actuation of such lowermost order transfer pawl to enter the fugitive one in the lowermost order of the accumulator. If this entry of one requires a tens transfer into then'ext higher order or-orders; the associated transfer pawls will be conditioned and sequentially operated during such'second' transfer wave.

Referring-"to Fig. 5,'- the 'highermcst -order ac- I cumulator gear 'BEia is provided with a special tooth II3 which, when the gear is located in 'zero-registration, as illustrated, lies intermediate the ends of the tails of a pair of opposed by-pass pawls II4 and IIS pivotally supported at IIS and III respectively on a plate H8." The pawls are normally held-in their illustrated positions by a tension spring"206-extending be-- tween tails thereon to hold the tails against a collar 26! on the shaft I8. i 7

Plate H8 is pivotally supported on the shaft I8 and is settable by the tooth II3 into either of two positions and held in either position by a centralizer II9 pivotally supported at I20 on the leftmost accumulator brace plate 191;. 'A spring I2I extending between the centralizer'and the suitable portion of the accumulator frame maintains a pin I22 on the lower end of the centralizer in engagement with one orthe other of two detent" g notches I23 formed in the plate H8. The latter plate is suitably secured to a fugitive one entry bail I24, extending the length of the accumulator andpivotally supported at opposite ends thereof on the accumulator shaft I8 (see also Figs. 7, 8 and 9). The end of the bail I24 adjacent the lowermost order of the accumulator (Fig.' 8) is bifurcated to embrace a pin I25 attached to an arm I26 freely pivoted on the accumulator shaft 11 and provided with a tooth I21 arranged to either underlie or overlie the ear 93 of the lowermost order transfer pawl I84a.

When the accumulator is in a positive condi tion, the plate II8, bail I24 and arm I28 are in their positions illustrated in Fig. 8 with the tooth I2'I underlying the ear 93 of transfer pawl I84a. Now, when a negative overdraft occurs due to over-subtraction, the accumulator gears, including gear 6512 (Fig. 5) above the highest order being digitized, will be turned clockwise from zero" into nine registration during the first transfer wave in the following transfer phase. Thus, as the highermost order gear 65a ea c ee sw se ans... n r men from its z ta?- position shown in Fig. itstooth I I3 will pickup the by-pass pawl II4 to rock the plate H8 and hail I24 counterclockwise to'rock arm I28 (Fig. 8) clogkwise, causing its tooth I21 to raise the transfer pawl I ,8 4a into its subtract transfer condition hown in the dot and-dash lines I.84a. Thus, duringthesecond transfer wave the lowerost or er transfer. pawl I M will be ved ormally. hrou h itse t ating strOke, enterin the fugitive one into the lowermost order gear. It should he noted that the plate II8, bail I24 and; arm. 26. wil beheld n. t e o ed n stiqns by thecentralizer, I I 8 as long as the accumulator remainsin'its negative overdrafted conditign. Therefgre, as the actuator pawl I84a moyea e warsllr h ou its a e i g st o e t. wi fidua x. more. o. neutral p sit n a d u on etur in the ea .1; wi come o e t under the tooth L21, which at this time will be qoatedln. h doteand-da h. i posi io ma.

It will be noted that the transfer cam assoc at dwit thelew rm st rder ac umu ea e-s awl. n. 8 r vided, with a. single lo e only which soarranged as to actuate the transfer pawl I8,4 a at the start of the second. transfer ere o y.-

nesatiyeqverd a condition s c ected r aslqina bt h acc m r an amount eate ha hgd fieit occu in in. an of the mulate eearsmelud ns. the highermost order gear 81g. 5) abovethe orders being i itized llbe advanced ro i traiqntia. ze o? egi trat on. C s qu tly. th 9ll will mqileeeun r ockw se from its full line positign, picking up the pawl I I5 to rock the pl 'a tie I I8 bail I ,24 and arm I28 back into their lil l td 11 x1 .Y posit ons s w in. Fi 5 and B Thus, the ear I2 I .of arm I2 6 will pick up the ear 93 9f transfer pawl I 844; to position the pawhits additive transfer position shown in Fig. 10. Therefore, during the second transfer wave of the tens transfer phase, the unit one will be addeddnto the lowermost order of the accui r. e p ate ail rm 12.

w lll"there after remain intheir setpositions as long as the accumulator contains a positive iiisiimi herejn.

a r la ively aree mqs t. s. p m a n hfifi i i llaisb ewhieh a e he accumulator fi! hrq h ne or more v ti'o'ns in an additive direction, thetooth I I3 will merely wipe over the pawl II4 without altering the position "of, the plate" I I 8," The same will be true when'subtracting relatively largeamounts from the'iaecuinulator after same assumes a negative condition in whichfcasethetooth II? will merely wipe over pawl II5,in a clockwise direction' without altering" the position of the plate I I8 from its negative overdraft position.

Means are provided for locating the transfer shaft 9 5,in"a full'cycle position regardless of any play which might occur in the. train of gears extendingbetween this shaft and'the main drive shaft 5 I. Referring to Fig. 11, a centralizer disc 2 68 is securely fastened to the shaft 9.5. and is provlded with a'detent notch therein normallyengaged by a roller 269 carried on. a centralizer arm 218 pivoted at 2' and urged clockwise by spring 212' to yieldably hold the roller 269 in the notch of the disc 268.

Accumulator controls As mentioned hereinbefore, the various control bars I0, I3, I4, I] andIBiFigs. 3, 4 and 5) are 12 irqvi e l er. aelr lli s e95 e ie ia .op ratiqii of t e mes es sewer-season n h r is n and? we n h ecsvmulat t me the 94 mulator gears 65 with either the upper rack sections 83 or thelower. rack sections 64 of the racks I9, depending. upon the type of operation to be performed- For thi ri rp e m han is rimvidedwhich isu'nder control of the different con trol bars and al'so thefugitve one control mechanism for determining and efiecting the positioning of .the accumulator.

In totaling and. sub totaling operations, the positioning of the accumulator is under the joint control of the barsv Ii 18 the fugitive one. mechanism." when amounts. being totaled or sub-totaled'from the accumulator are positive in nature, the accumulator.is'loweredintomesh with the rack sections 84. of the racks I8 so that they are returned backwardly to zero registrations. However, when amounts of a negative nature are being totaled or "sub-totaled the accumulator is meshedwith rack sections so that they are all advanced forwardly to "nine" registrations.

The aforemntionedbox cam 82 (Fig. 3) is propivotally" connected 'to" a three-armed lever I3] which is pivotally mounted o a rod. I32 The cam follower urged counterclockwise by a spring'l33 to press 'a'roller, I34 against a cam I keye'donthe drive shafts]. 'Cam 35 has a high portion extending substantially'o'ver one-half, of its periphery whereby it. will normally rock the cam follower, I3I and thereby drive and hold the hook I30" rearward d'iiringapproximately the first half of a. machine. cycle." During additive operations, or when. the. machine is at rest, the hook I30 is held in'its raised position illustrated in Fig. 3 by a, tension spring I31. in the hook and embracesjthe pin II2'I'ivhereuponrotation of the shaft 5|. underffcontrol of..=theadd -bar will cause a rearward.niovementfof'the hook I30 to rock the cam 82 clockwise. action will raise the accumulator. into its additive position.

For thepu'rposejofI-liicating the hook I38 in a lowermost. subtract control position or an. intermediate 'nonr-a'dd position wherein it is ineffective to actuateeither oruie p'insI'I2fI or H28, a. 0on trol bar I38 is'ope'ratively. connectedto the hook and is supported-for longitudinal movement by a pair of parallel links I39 and l'4fllpivotally suspendedfromtheframe bypins l4]. The bar I38 has two inclined active. camming surfaces I42 and I43 formed thereon and underlying the aforementioned'pinsllliand I46 actuated by the subtract bar I3 andnon-a'dd bar I4, respectively.

The bar I38 connectedby a pin and slot connection ll4'to,'a .bell'crank I41 pivoted at [48 and, in turn, coupled through'ja pin and slot connection' I48 to thejforwardendr'oflthe hook 'I 30.

The camming surfaces I42-and. I43 are so 'arranged that,'up on depression ofthe subtract bar I3, the control bar I3'8jwill bemoved forward its fullest extent whiehj'through. the bell crank I41, will lower the hook I3I):.,to cause a slot I50 therein to embrace the'pin II'28 on the box cam 82. Accordingly, upon subsequent rearward movement of the hook, the boxcamwill be rotated counterclockwise tollower the accumulator into its sub.- tractive .DOsitioIil V l The contour of, thqcamming surface I43 is such that; depressionof the non-add bar I4,wil1v move the hook I 3Q. .t an intermediate. position wherein it willb ine fective. toactuate the box.

13.. cm and thus the accumulator will remain in its neutral position during the subsequent cycle. In order tonormally maintain the box cam 82 and therefore the accumulator in their neutral positions when so placed, a centralizer 1 I is provided, being pivoted at I52 and urged counterclockwise by a spring I53 to force aroller thereon into a detenting depression formed on the lower periphery of the box cam.

Meansare'provlded for moving the control bar I38 'forwardly upon depression-of the total and sub-total bars to effect totaling and subtotaling-.-operations only when such totals and sub-totals are of a posltivenature. For this purpose the control bar I38 is ineffective to be actuated directly'by the totaland sub-total bar actuated pins I BI and I62. Instead, the bar is provided with a pin I55 (see also Fig. 4) extending directly behind the shoulder of a second control bar I56 suspended by links I51 and I58 also pivoted at I4I independently ofrthe links I39 and I48. Inclined camming surfaces I58 and I68 on the bar I56 underlie the pins I 6| and I62, respectively. The bar I56 is normally held in its rearward illustrated position by a spring I63 tensioned between a frame stud I64 and an interponent I65 pivoted at I 66, to the control bar. Normally, the spring l6 3-holds the interponent I65 in 'such a position thata shoulder I61 at the forward end thereof lies directly behind the pin I55, thus coupling-the bar I56 directly to the control bar I38, Therefore, depression of either the total or sub-total bars and consequent forward movement of the control bar I56 will normally, through the pin I55, carry the control bar- I38 (Fig. 3) therealong to set the hook I38 in its lowermost or subtract control position. Depression of the total and sub-total bars will,

- as described hereinbefore, cause operation in the machine to clear an amount from the accumulator and print the same in the case of, totals or to clear an amount and print the same and thereafter re-enter this amount in the case of sub-totals. In totaling, the accumulator is held in mesh with the racks during the first half of the cycle, as noted hereinbefore, by th cam I35 (Fig. 3). However, in sub-totaling operations the accumulator is held in mesh with the racks throughout the major portion of the cycle. To this end a second cam 288 is mounted on the shaft 5I in juxtaposition with cam I35 and is provided with a high portion extending around the major portion of the periphery thereof. This cam engages a roller 28I (Fig. 4) normally in alignment with the roller I 34, the roller 28I being mounted on a bell crank 282 pivoted on the rod I32 and urged counterclockwise by a spring 283. A slot 284 is formed in the bell crank 282, which slot is normally coextensive with a shorter slot 285 inthe lever I3I.

A pin 286 carried on a slide 281 slides within one or both or the slots 284 and 285 depending upon its position longitudinally of the machine. Th link 281 is connected at its forward end to the lower end of the arm I44 associated with the sub-total bar, the latter extension 288 of which carries the aforementioned sub-total bar actuated pin I6I. Normally, when the sub-total bar is in its raised position, the link 281 will be located rearwardly as illustrated whereupon the pin 286 will be located solely within the slot 284. However, upon depression of the sub-total bar the pin 286 will be moved forwardly within both 51085284 and 285. In this condition, 1. e. during a sub-totaling operation, the two elements I3I 14 and 282 will move as a unit and the cam 288 will therefore become effective to control the hook I38 and thus hold the accumulator enga ed with the drive rack throughout the major portion of the cycle.

Means are provided for disabling the interponent I65 when a negative overdraft condition is existent in the accumulator so that depression of the total or sub-total bars to effect a total or sub-total operation will be-ineifective to set the accumulator into its subtract condition. Control of the interponent I65 is derived from the control plate I I8 (Fig. 5) which, it will be recalled, is moved counterclockwise from its illustrated position to a second position about the shaft 18 when the accumulator is set in a negative overdraft condition. For-this purpose, a link I18 is pivotally connected between an arm extending from the plate H8 and a three-armed lever I1I pivoted on the hereinbefore mentioned pin 42 independently of the clutch dog 4I. One arm of the lever I1I is connected to a link I12 (Fig. 4) having a slot I14 at its upper end guided over a frame stud I 15. A pin I16 extending from the link underlies the interponent I65. Therefore, as the plate H8 is rocked counterclockwise, incident to a negative overdraft occurring in the accumulator, th link In will be raisedto rock the .interponent I65 counterclockwise .to lower its shoulder I 61 from behind the. pin 155. Therefore, while in this condition, depression of either the total or sub-total bar will be ineffective to actuate the control bar I38 and the hook I38 will remain in its illustrated raised position to raise the accumulator into an additive position during the subsequent totaling or sub-totaling operations.

Totaling stop controls Means are provided under the control of the total and sub-total bars I1 and I8 respectively, to arrest the accumulator gears in their zero registrations in the taking of positive totals and sub-totals or in their nine registrations during taking of negative totals and sub-totals. As shown particularly in Fig. 7, a series of totaling or zero stop levers I18 are keyed to the shaft 18 in co-operative relation with ears 94 formed integrally with the various accumulator gears 65. During totaling andsub-totaling operations, the shaft 18 isrocked counterclockwise a slight amount to position ears I19 on the arms I18 in blocking relation to the ears 94 regardless of whether the gears are rotated in an additive or subtractive direction.

The shaft 18 and totaling stop arms I18 are rocked counterclockwise by power under control of the total and sub-total bars and to accomplish this arm I88 (Fig. 4) is secured to the shaft 18 and has a pin and slot connection IBI with a floating lever 482. The latter normally rides on a stationary frame pin I83 and is pivotally connected to the lower end of a vertical link H84. The upper end of the latter is connected to the middle of a cross link I85 connected at the opposite ends thereof to the pins I6I and I62 underlying the stems of the control bars I1 and I8.

Upon depression of either of these two control bars the links I85 and II 84 will be lowered sufficiently to rock the lever 482 about the pin I83 to position a shoulder I86 thereon in the path of the pin I81 carried by the aforementioned cam follower 282 (see also Fig. 3). Thus, as the latteris rocked clockwise at the beginning of a total or sub-total operation as explained hereinbefore, pin I81 will force the lever 482 forwardly to rock theme; flrandsh it 1 c un erclockw s a a nst. he. a tion of: a suitab e sprin not. shown)- s a o. oa rall th ltotclina toaarms. i' iiint blocks relation w ih he ars .;4; onithe a u u to gears 65. Thus, as the machine continues; its yc e; he cks. lazwi be dr ven forwa rota ins. hejse rs; 65 11 th ren ac itir r s btra direct on d nendina up th i c ndition of.

th ccumu ator. untflthey are. a r sted by t ton 11 he aokawi l: therei m and: n

pos t ons mechanic ll e esen in it e he.

re ster n theinr ntmgmechanism to nr nt hi Valuer Example of 'ty-aeaeg qtive total operation d moreclearln understand; the tim tiozrof: theme-china during-taking of av negative totalthefollowing. example. is given.

Assume.thatthe accumulator registers. a. positiveamountof-i456i therein and; that the sumof 487; issuhtracted: therefrom. Since. the amountv subtraciedfrom the accumulator. isgreater than the: amount already contained therein. it evi-v dentthat. a fugitiverone will-.be subtracted; from the. lowermost order and-g if: a total taking operation is initiated at. this point the. accumulator gears will be. advanced. to nines to register on.

the racks as;true;negative-.totals., The problem isrrepresented asifollows:

advancing accumulatorgears to nines registration.

At the completionpf. the digitizing phase of a subtract cycle andbe fore the transfer phase has commgnood, the accumulator will stand at 000079.

with the transfer. pawls I84. in the tens and hundreds orders set in subtract tens. transfer condition; Thereafter, the accumulator is raised from its subtract position to neutral. and the transfer phase commences, rotating the transfer shaft 95 clockwise to cause the, earns 88 to. actuate all transferpawls commencing with, the tens ordorer or h an f r paw 2 he. tens order will retract its accumulator gear to 6;

and the pawl in the hundreds order willretract its. gear to o r g y t e. ho san s rde paw will be setin transferring condition and immediately thereafter it will be actuatedto retract its gear to 9 This retracting process will continue through all of the highermost,ordersleaving the accumulator atthe end of the first. transfer wave at 999,969, Itetraction of; the highermost order gear 85:: (Fig. 5), from to 9. will, through the plate I18, bail I24 and arm I26, set the units order. transfer pawl I 8 4 a (Fig. 8) insubtractive ransfer condition before the second transfer wave occurs. A continued rotation of the trans-. fer shaft throughitssecondjhal f revolution will.

thus actuate the units pawl, retracting its gear from 9 to 8, leaving the accumulator to register 999968.

RQckingof-bail I2 twill also, through the link--.

1e are 1 ,1. I a 12. E nternment Hi QQQ Y J- QWN..Whenthe tota bar it s. dep e sed tob in, a. t ta actuat o of; theontrol bar L56. will; be inefiective to set the ook- 0 om ts o a1 add pos tion-to its sub,-

tractposition, Accordingly. the accumulator will be, raised; to' rotate.- the accumulator gears, additiyelyi t ward. their nines positionsit they were not already there,. atv which time they. will be arrestedbythe totaling stops, I18. Thus, the units order rack will: beadvanced oneincrement from eight to. nine and; the tens order rack will be ad-- vanced! three increments from six to. nine, thus registering 31 in these orders.

Zeroleuel cut-om mechanism Meansare provided-for automatically arresting operation: ofthe machine: as the accumulator overdrafts in changing froma. positive to 9, negative nature or viceversa soas to physically indicate to the operator the fact that an overdraft has occurred; For this purpose a link I280 (Fig. 5) is connected between the three-armed lever I:'| I and an arm I28I pivoted at I282. The arm |-28I is provided with a roller I283 positioned in a' path arrangedto tercept acamming foot I284 on-- the aforementioned hook 29- which it will berecallednormallycouplesthe clutch control bar 323 to the clutch dog 4-I. During repeated-subtract or 'add operationsthe -bar 323 is held slightlyforward of its illustrated position and thus maintains the camming' foot IZM -in the-path of roller I283. Therefore, upon anoverdraft occurring, the plate I-IB- will; be rocked in one direction or the other depending upon the nature of theoverdraft and will, through the link IIII etc.,

likewise rockthearm I28I causing the'roller I283 Visual overdraft indicating device Means are provided for visually indicating the nature and amount in the accumulator, i. e., whether the amount is negative or positive. Referring to 5, indicator lever I2B 5 is pivoted on a, frame pin I285. and-is coupled through a pin andslot connection I281 tothe three-armed lever I;I' I; thus partaking of the movement of the latter as the plate H8. is shifted from one position. to another upon the change in character of the amount in the accumulator. A visual indicator 288 is mounted on the upper end of the lever I285 and upon overdraft from apositive toa negative condition the visual indicator moves to the position shown by the dotrand-dash lines. 288a, directly below a transparent window 289 formed in the cover 29.0 of the machine.

Symbol-.gnintingcontrols In order to indicate on the tape the type of factor or totals printed, an appropriate symbol is recorded along the side of each value which is the result of any operation except addition.

Referring to Fig. 17-, a single symbol control rack I-is provided. The latter is guided for fore and aft movement by shaft 239 and a frame pin-I91 embraced by slots I92 and I93, respectively, formed in the rack. A spring I94 contin 1. 85.. 4 and 5.); render t 17 ually urges the rack forward to follow the aforementioned rack drive shaft 52- as the latter moves fore and aft of the machine.

A rack section I95 on the rack meshes with the gear I96 forming part of one of the pinion assemblies I5 (see Fig. 1) entrained with an associated printing wheel (not shown) similar to the wheels 66 but having thereon appropriate symbol characters in lieu of the usual numeral characters.

Means are provided for preventing the symbol rack I90 from advancing from its illustrated home position when an add operation is being performed, it being desired not to print a symbol during such operations. For this purpose, a latch I9! is pivoted on the frame pin I9I and is provided with a pin I98 (see also Fig. 4) extending into a slot in the clutch control bar I56. When the bar I56 is in its rearward position, as is the case when the machine is at rest or when the add bar I0 only is depressed, a shoulder I99 on the latch is located directly in front of a pin 200 on the rack I90. Therefore, since the bar I56 is not actuated during an addition operation, the latch I91 will remain in its latching position, preventing movement of the rack I90 as the rack drive shaft 52 moves forwardly. Suitable means (not shown) are provided to prevent the symbol type wheel from moving'to printing position when the rack I90 remains in its home position. However, during subtract, non-add, total, and subtotal operations, the bar I56 will be actuated as noted hereinbefore and the latch I91 will consequently be rocked to allow the symbol rack I90 to follow the drive shaft 52 until arrested by the control bars, as will now appear.

Two shoulders 20I and-202 are formed on the rack I90, the former being normally spaced one increment behind, the pin I45 when the latter is lowered by the subtract bar I3. The shoulder 202 is spaced two increments behind the pin I46 when the latter is lowered by depression of the nonadd bar I4. These shoulders thus limit the forward movement of the rack by one or two increments depending on which of the bars I3 and His depressed.

A slide 203 is mounted on rack I90 having slots therein embracing pins 204 extending from the slide. Two shoulders 205 and 206 are formed on the slide 203, the former normally being positioned three increments behind the pin IBI when the latter is lowered by the sub-total bar I8 and the shoulder 206 being located four increments behind the pin I62 when the latter is lowered by the total bar II. A spring 201, which is considerably weaker than spring I94, is tensioned between the slide 203 and a stud 208 on the rack I90 to urge the slide into its illustrated position and a latch 209, pivoted at 2I0 to the rack, is provided with a shoulder 2I I to normally lie directly behind the slide 203 to lock the same in this position relative to the rack.

A spring 2I2 extending between a stud on the rack and the'latch 209 retains the latter in blocking relation to the slide 203 when the accumulator is in a positive or normal condition. However, upon an overdraft from positive to negative condition, a pin 2I3 on the aforementioned three-armed lever III will be lowered to its alternate position shown by dot-and-dash lines 2I3a so that were a total or sub-total operation to be efiected while the accumulator registered a negative amount, a tail of latch 209 would engage the pin 2I3 and move about its pivot 2I0 to a position releasing the slide 203. Therefore,

18 the slide, upon striking one or the other of pins I6I and I 62 would yield an amount equal to two increments of movement of rack I90 thus permitting the rack to advance further than normal to indicate a credit total or credit sub-total as the case may be.

In certain cases it may be desirable to omit or disconnect the credit balance feature while retaining the zero level cut-oil and the visible indicator devices. In such cases the overdraft control plate 8, pawls' I I4 and [I5 and linkage I10, III, 280, 28I and 295 would be retained while the link I12 (Fig. 4) and bail I24 would be removed. It would then. be desirable to return the visual indicator to its hidden position (Figs. 5 and 6), indicative of a positive condition of the accumu lator, upon taking of totals, if the indicator had previously been setto indicate a negative con,- dition. For this purpose, the indicator lever I285 is provided with a tab 295 (Fig.- 6) lying directly behind a bail .295 pivoted at 291, and provided with abifurcated arm 298 embracing the total bar actuated pin I62. Therefore, depression of the totalbar will rock bail 29G counterclockwise and, through thetab 295, will re; turn the indicator to itspositive indicating .or hidden position, if not already there.

Having thus described theinvention whatwe desire to secure by United States Letters Paten is:

1. In a calculating machine, the combination of an accumulator including denominationally arranged reversible accumulator elements each having a positive zero position and a negative zero position, differential actuators adapted to drive said accumulator elements in additive or subtractive directions, means including a control member settable into a first position and operable to cause said actuators to drive said accumulator elementsin an additive direction, said control member being settable into a second position and operable to cause said actuators to r drive said accumulator elements in a subtractive direction, totaling mechanism including a depressible total bar, a zero stop device rendered effective by said tota l .bar upon depression thereof and adapted to arrest said accumulator elements in said positive zero positions upon movement of said accumulator elements in said subtractive direction, said zero stop device being adapted to arrest said accumulatorelements in said negative zero positions upon movement of said elements in said additive direction, means normally maintaining said control-member in said first position thereof, means including an interponent operable by said total bar upon depression thereof for normally setting said con- J trol member in said second position, and means actuated by the accumulator element of highest denomination and responsive to a change in the character of the sum represented by said accumulator elements for rendering said interponent ineffective to set said control member and for advancing the accumulator element of lowest denomination an amount corresponding to one unit.

2. In a calculating machine, the combination of an accumulator includin denominationally arranged reversible-accumulator elements, each having a positive zero position and a negative zero position, differential actuators adapted to drive said accumulator elements in additive or subtractive directions, means including a control member settable into a first position and operable to relatively adjust said actuators and accumulator elements to permit driving the latter in an additive direction, said control member being scttable into a second position and operable to relatively adjust said actuators and accumulator elements to permit driving the latter in a subtractive direction, totaling mechanism including a depressible total bar and a zero stop device controlled by said total bar upon depression thereof and adapted to arrest said accumulator elements in said positive zero positions upon movement of said accumulator elements in said subtractive direction, said zero stop device being adapted to arrest said accumulator elements in said negative zero positions upon movement of said accumulator elements in said additive direction, spring means for normally maintaining said control member in said first position thereof, means normally operable by said total bar upon depression thereof for setting said control member' in said second position, and means controlled by the'accumulator element of highest'denomination and responsive to a change in the character of the sum represented by said accumulator elements for'rendering said last mentioned means ineffective and for advancing the accumulator element of lowest denomination an amount corresponding to one unit.

'3. In a calculating machine, the combination or an accumulator including denominationally arranged reversible accumulator elements, differential actuators adapted to drive said accumula'tor elements in additive or subtractive directions, means including a device movable between two positions to cause entry of one unit; into the accumulator element of lowest denomination, a pair of by-pass pawls on said device, one of said pawls being engaged and positively moved by the accumulator element of highest denomination to a position out of the path of said last-mentioned accumulator element upon movement of the latter from zero to nine registration whereby to move said device from a first one of said positions to the second, and the other of said by-pass pawls being engaged and positively moved by said accumulator element of highest denomination to a position out of the path of said last-mentioned accumulator element upon movement of the latter between nine and zero registration whereby a,

to move said device from said second position to the first.

4. In a calculating machine, the combination of an accumulator including reversible accumulator elements; drive racks therefor adapted to drive said elements in additive or subtractive directions, mean for adjusting said accumulator into either of two positions from a neutral position relative to said racks to permit driving of said accumulator elements in one or the other of said directions, tens transfer mechanism operatively associated with said accumulator elements and conditioned thereby for tens transfer from on element to the next higher denominational element, means other than said elements for actuating said tens transfer mechanism, and means responsive to movement of said accumulator into one of said two positions thereof for rendering said actuating means inoperable.

5. In a calculating machine, a combination of an accumulator including reversible accumulator elements; drive racks therefor adapted to drive said accumulator elements in additive or subtractive directions, means for adjusting said accumulator into either of two positions relative tb said racks to permit driving of said accumulator elements in one or the other of said directions, tens transfer mechanism operatively associated with said accumulator elements and conditioned thereby for tens transfer from one element to the next higher denominational element, means other than said elements for actuating said tens transfer mechanism includin a train of intermeshed gears, and means operable by said first mentioned means upon movement of said accumulator thereby into one of said position for de-meshing one of said gears from another.

6. In a calculating machine, the combination of an accumulator including denominationally arranged reversible accumulator elements, differential actuators adapted to drive said accumulator elements in additive or subtractive directions, drive means including a clutch for actuating said actuators, a. device movable between two positions to cause disengagement of said clutch, a'pair ofby-pass pawls on said device, one of said pawls being engageable by the accumulator element 'of highest denomination upon movement of the latterfromlczero to nine registration to move said device from: a first one of said positions to the second,- and'th'e other of said bypass pawls bein 'enga'geable by said accumulator element of highest denomination upon movement of the latter between nine and zero registration to move said device from said second position to the first.

7. In a calculating machine, the combination of an accumulator comprising reversible accumulator elements, differential actuators adapted to drive said accumulator elements in additive or subtractive directions, 'drive means including a clutch for operating said actuators, a device movable between two positions for entering one unit into the accumulator element of lowest denomination, a pair of by-pass pawls on said device, one of said pawls being enga'geable by the accumulator element of highest denomination upon movement of the latter from zero to nine registration to move said device from a first one of said positions to the second, and the other of said by-pass pawls being engageable by said accumulator element of highest denomination upon movement of the latter from nine to zero registration to move said device from said second position to the first, a depressible control bar, clutch control mechanism controlled by said depressible bar upon depression thereof for effecting engagement of said clutch, and means actuated by said device upon movement thereof for rendering said clutch control mechanism ineffective.

8. In a calculating machine, the combination of an accumulator including reversible accumulator elements; actuators therefor adapted to drive said elements in additive and subtractive directions, means for adjusting said accumulator into either of two positions from a neutral position relative to said actuators to permit driving of said accumulator elements in one or the other of said directions, tens transfer mechanism operatively associated with said accumulator elements and conditioned thereby for tens transfer from one element to the next higher denominational element, drive means other than said elements and including a power transmission mechanism for operating said tens transfer mechanism, and means operatively connected to said accumulator and responsive to movement of said accumulator into one of said two positions for operatively disconnecting said power transmission mechanism.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Pasinski Aug. 26, 1930 Foothorap Jan. 5, 1932 Butler May 24. 1938 10 Anderson Sept. 27, 1938 Fuller Mar. 11, 1941 Number Mehan Apr. 24, 1951 

